HONG KONG (Reuters) – Chaotic scenes erupted in Hong Kong early on Wednesday as thousands of demonstrators stormed a key road next to government offices to protest against a proposed extradition bill that would allow people to be sent to mainland China for trial.

Television pictures showed thousands of protesters rallying in and around Lung Wo Road, an important east-west artery near the offices of Hong Kong Chief Executive Carrie Lam, as hundreds of riot police warned them to stop advancing.

Some protesters erected barricades to block traffic in the heart of the Asian financial center, with many defying police calls to retreat, in scenes reminiscent of pro-democracy protests that rocked the city in late 2014.

Embattled leader Lam said she would press ahead with the controversial legislation despite deep concerns across the Asian financial hub that triggered on Sunday its biggest political demonstration since its handover from British to Chinese rule in 1997.

Demonstrators from across a wide spectrum of Hong Kong society began joining the overnight protesters earlier on Wednesday as businesses across the city prepared to go on strike.

The bill, which has generated unusually broad opposition at home and abroad, is due for a second round of debate on Wednesday in Hong Kong's 70-seat Legislative Council. The legislature is controlled by a pro-Beijing majority.

Lam has sought to soothe public concerns and said her administration was creating additional amendments to the bill, including safeguarding human rights.

In a rare move, prominent business leaders warned that pushing through the extradition law could undermine investor confidence in Hong Kong and erode its competitive advantages.

Sunday's protest, which organizers said saw more than a million people take to the streets, in addition to a snowballing backlash against the extradition bill could raise questions about Lam's ability to govern effectively.

STRIKES, GO-SLOWS

Protesters rallied just a stone's throw from the heart of the financial center where glittering skyscrapers house the offices of some of the world's biggest companies, including HSBC.

HSBC and Standard Chartered (LON:), in addition to the Big Four accounting firms, had all agreed to flexible work arrangements for staff on Wednesday, Hong Kong media reported.

Strikes and transport go-slows were also announced for Wednesday as businesses, students, bus drivers, social workers, teachers and other groups all vowed to protest in a last-ditch effort to block the bill.

The Catholic Diocese of Hong Kong called on the government not to pass the bill "hurriedly" and urged all Christians to pray for the former British colony.

Embattled leader Lam, who warned against "radical action" at the latest protest, is a Catholic.